Automatic depth controlling mechanism



May 4, 1943. T, BR'GWN, 2,318,194

1 AUTOMATIC DEPTH CONTROLLING MECHANISM Filed 001;. 20, 1939 3Sheets-She'et l INVENTOR;

y 1943- T.BROWN- 2,318,194

AUTOMATIC DEPTH CONTROLLING MECHANISM Filed Oct. 20(1939 s Sheets-Sheet '2 May 4, 1943- T. BROWN 2,318,194

AUTOMATIC DEPTH CONTROLLING MECHANISM Filed Oct. 20, 1959 s'snee cs-shet :s

. INVENTOR:

@EYS.

Patented f4fi94$ siren,

Es PATENT oF-Fi AUTOMATIC DEPTH CONTROLLING 1 V MECHANISM' q Theophilus Brown, Moline, 111., assignor, to I Deere & Company, Moline, 111., a corporation;

.plements having'one or more ground working tools, the operating position of which may be I'varied and, further, in which the tool is adapted to be raised entirely out of engagement with the ground for transport or other purposes.

The object and general nature of. the present i invention lies in the provision of automatically operating means for gauging the operating depth of the ground working tool from the ground surface so that through suitable operating means,

preferably deriving power from the tractor or other propelling means, the ground working tool is constantly maintained at a-giyen depthof working tool may take with' respect to thetractor or other propelling 'means.-. More specifically, it

t is a feature of the present invention :to provide Q 1939, Serial Nb; 300,371 g I .detailed description 'of'the preferred structural I t in the accom f panying drawings. I

,m the drawings: r I Figure 1 i'saperspective view'of the rearend the principles of the incorporated;

. plowing position}; i r a Figure 3 is a view similar to Figure. 2, showing v the plow bottom in'shallow plowing position; I Figure 4 is a view similar to Figure 2, but show- '15 ing t e pposite side of the machine. and illuspenetration, which may be adjusted, independ- 'ently of the relative positions which the, ground means r'iding along the ground surfacetraver'sed by the implement and operating to control other Qmeans that raisesiand lowers the tool,- as required. Further, it is a feature'of this invention, "to provide a pair of independently movable groundengaging elements'associated with the ground working tool, one of the elements forming a part of the mechanism for raising and lowering the tool while theother elementv serves to control the operation of the raising and lowering means to automatically maintain the tool at "the desired depth. In this connection it is a still further feature of the present invention to ar range the parts so that said one element takes the reaction of the raising and lowering means but the other element is subjectedto practically no load other than its own weight, thereby protrol.

Another feature of the present invention is the provision of raising and lowering means for the ground engaging tool, the raising and lowering means being of a hydraulic self-locking arembodiment which is illustrated of a tractorand associated implement, in which Figure 2 is aside view of the rear portion of the machine, showing the plow bottom in' deep trating'the gauging connections by whiclr l'the the ground surface;

the parts-a'djuste'd for shallow plowing; I

Figure 6 is a view similar to'Figuresiand i but at. a larger scale, showing the operationgf their automatic depth controlling means;

Figure '7 is a perspective view of a portion of;

the hydraulic valve controlling-mechanism; and Figure'8 is a separated view ofthe parts shown Y inFigure '1.

' viding an extremely accurate and sensitive con- Referring now more numeral 2 indicates the tractor to which the imcrank case and transmission housing 5 of which serves as a part of the frame, and a rear axle housing 6 having tubular sleeve extensions 1 and ;8 in which two axle shafts!) and ID are journaled.

The tractor Z is provided with front wheels (not shown) "and rear driving wheels I l, the left rear 1 wheel being removed from the axle'shaft 9 in Figure 1, in order to. show more clearly the gauging and depth adjusting parts; of the machine with which the present invention is' more particularly concerned.

The tractor 2 is provided with mars mechanism, indicated in its entirety by thereference numeral l5, which is preferably hydraulically actuated and includes a transverse rockshaft' I6 actuated by suitable hydraulic mechanism under I the control of valve means having a valve actuating arm l2. Preferably, the hydraulic mechanism includes a pump driven from the tractor motor '4, a double acting cylinder and piston ar- 7 rangement for rocking theshaft. it from one present invention have been e 5 is a view similar to Figure 4, showing particularly toiFigures 1 Y to 3, the reference numeral lindicates, in its entirety, a plowing implement and the reference 7 valve levensuch as position into either of two operative positions.

atitsrear end and carrying a V Obvious y;

, ing tools may beemployed;-if desired. Thefront end of the plow beam -20 i r with the tractor by; suitable hitch means 25 so I (that the. plow beam 20,-and the furrow-,2 opener 122 cally relative to the,

1 dependently of variations, in

' ple, when traversing the upper link 3| ,to 3), by means of which is carried by the plow beam 20 and passes tical direction about a transverse axi in a block ing movement relative to the position to the valve means at other under the control of the 12, the valve mechanism being disposed in a section l1 which forms a part of the rear axle housing 6 when the tractor 2 is provided with hydraulic power lift means as shown.

' The power lift mechanism l may take the gendrawings, with v forward connection of the plow beam 20 with the hitch 25 is arranged to provide for a limited amount of lateral swinging movement.

The furrow opener 22 is arranged to hav its operating depth determined by the position of the gauge wheel relative to the plow beam 20 and the furrow ,opener 22? secured to; the rear end thereof. To this end, 'theforward' end of the link 35 is looselypivoted, as at 55, to one arm 55 of a bell crank 51 which preferably is welded j or otherwise fixed to a transverse bar 58, the ends actuating the valve into either of'its fully raised or fully'lowered positions the. valve means I2 arranged so that it may be moved in a position to lockthe piston, and hence the power lift shaft l6, cylinder against movement in at leastonedirection, along the lines of the hydraulic power lift shown in the patenttoHaroldlBrown, No. 1,929,- a 804, issued October 10, 1933. :Obviously, of course,

any other suitable form of power lift mechanism.

f either doubleor single-acting, may be employed in thepresent invention,

so long as such mechanism' is of the typewhich ;n 1ay raised or lowered, as desired, or held in any intermediate position, in any suitable manner, as by moving a l2, from a neutral or locked In order to best illustrate the principles of the 20cu'rve'd, as at 2L.

furrowIppener 22. of course, otherforms of ground workis r pivotally. connected carried thereby, may swing generally vertimove along in operating position no're' or'less inthe position of the tractor relative thereto, as may occur, for exam rough oruneven ground.

has been omitted and in any position in its of which are supported for rocking movement in a pair of bracketsfil and 62 fixed to the tractor in any suitablefimanner, as by having laterally outwardly turnedends 53 apertured to receive attaching stud bolts 54. The other arm 68 of the bell crank'51pivotally receives the rear end of a dink"), the forward end of which is pivoted to an arm H which forms a part of a power lift The power lift arm-12 is securely fixed to the squared righthandend of the po'wer lift rock shaft IS. The powerliftunit l5 of'the tractor =2 is under thecontrol of a handleyer'fi mounted on the upper'portion of the housing enclosing the powerlift mechanism by any suitable means; such as apairoflugs rockably receiv ing a shaft;18,fltoyone-end of'which the hand ries to the valve actuating arm l2,as.shown inFig- I presentinvention, the implement I is in the form of an-integral plow includingla generallylongitudinally extendingplow beam;

shaft l6 to be rocked lever 1511s fixed andthe other end of which car- 'niarrn 19 .whichfis connected byla link 80 me li ilnthis figurethe hand lever 15 and the valve arm l 2 are shown, in their neutral positions,'in which; the. power lift rock aitl B is locked against 7 movement in at least one direcr 'Ihe operation-of the, structure so far described is substantially-asfollows; 1,

*Whenitis desired to; raise the plow" bottom 22 from a deep plowing position (FiguresIandZ) to 40' tractor, and also'iaterally to some extent, whereby the plow bottom' 22 may a shallowplowing; position Figure 3) the, operator'm'oves the hand lever,1 5 forwardly, which actuates the valvemeansfl. and-causes the rock in a cl ck s ir ct as viewed in'Figures 2 and 3. Generally, thepower liftrock-shaft Hiis'adapted to be movedthrough a total angular displacement ofabout 160 degrees,

' A first gauge wheel'30 is-movably connected with thetool beam 20 by a pair of links 3| and 32, the links being pivotally connected to one another by a pivot pin 33 which also pivotally reextending operating link,

-is pivoted, as at 36--(Fi gures 1 which is pivoted by trunnions 4,1 for pivotal movement about a vertical axis in a yoke 48 which is fastened to a supporting structure 49 bolted to the underneath side of therear axle housing 6. Since the crank axle ,44 has both horizontal swinging movement and vertical swingport'49, it will be 40 extending downwardly andof this range ofmovement, the first part is utilized for securingdifferent depths of operation, the limits of which are shown i'nFigures 2 ceives the rear end of a generallylongitudinaliy 355. 1 The upper end of 7 a pivot bolt 35 .or the like 3 s5 auge wheel 30, the being pivoted to the position (Figure the'gauging arm and3. 'When: thepowerlift' rock shaft I8 is rocked to raise the plow out of itsdeep plowing 2), the rearward movement of 1i acts'through the link 10 and bell crank 51 toexert a forward-pull on the link 35', since the clockwise-Jotation of the farm 1| causes the counterclockwise; rotationv of the bell crank 51 This swings the upper link 31, the upper end of which is pivoted as at 36 m the plow beam .20, and exerts a thrust through the lower link 32' against the. crank axle 44 and the lower end of the link 32 crank axle by apivotipin or bolt 34. '-It .will be understood, of course,f'that at any intermediate positionof the furrowopener 22,'between that'shown in Figure 2 and that shown in Figure '3, the valve controlling lever 15 may'bereturned to. its neutral position, thus locking the power lift rock shaft I 6. ,together tractor carried sup-. seen that the gauge wheel 30.. g

is permitted to move with the plow beam 20 of the implement i," forming a part thereof. The 7 with the gauging :connections associated therewith; in that particular position. From-Figures 2 and 3, it will .be noted that the pivot 55 connecting the'forward end of the longitudinally extending. link 35"and the lower end or arm 56 of thebell crank 51 'is disposed closely adjacent the transverse axis definod by. the forward end. 45

- position,

1 i dated February of the crank axle 44, both of the axes and 5 .being, disposed adjacent the plow beam 20, where- .byrising. and falling movement of'the Plow beam 20. and furrow opener 22 as the tractor'passes over uneven ground will have no-materialefiect upon the position of the linkg 3I andsa and of the link 35 and'thejfront endor the crank axle 44 are pivoted tothe tractor.- Thus, the

inFigures2and3.

Mention was made'above of the'fact thatthe initial range r movement or the-rock'shatt I6 is 'utilized for adjusting the'furrow opener 22 for difi'erent 'fdepths 'of' operation, as indicated in Figures 2 and 3,: The next subsequent-range of movement of the rock shaft I6 is utilized'for; lifting both the plow beam 20 and'furrow opener .22, as well as the gauge wheel '30 itselfiout of ground engaging position and into'a transport position. f To this end, the power lift-arm 1-12 is provided with a bifurcated end between'the. two partsof, which a swivel block 8| is pivotally mounted on trunnions fl." 'The' block 8|: slidably receives a rod 8 the' lower -end ofw'which is .formed with a yoke that embraces and-ispivotally connected, as at 86, to the plow-beam 20,

I I'he upper end of thev rod 84 is" threaded-and receives a pair of adjusting nuts 88; The .posi:

tion. ofthe arm 12 and the length; of the. rod 86 are such that whenfthe'plowbottom 22 istin its most shallow plowing position',there 'is' sufiicient space S to permitthe implement-I itorrise and hence the position of the gauge wheel 30 relative 1 to the plow beam 20, even though theiront end 7 "According to the principles of the present invention, means is provided for automatically maintaining the plow bottom 22 at a constant plowing. depth, eventhough the pressure of the I plow; bottom may be such that the gauge wheel .30 no -longer-rides on the surface of the ground but sinks into. it some" distance; theamount of which depends upon the soil pressure, the speed of operation, v and the. softness 'of the ground. .Also; means is providedv for manually adjusting I the depth at which the'plow bottom 22 is-con- .stantly inaintained, all'withoutfinterference with themaisingoithe' implement into its transport position, g x

, Referringinow more particularly 'tdFigures 1,

4 and 5; the reference numeralIIllJ indicates a second; gauge; wheel .or pilot disposed alongside the .firstgauge wheel 30 I and 'niounted for rotation on an .auxiliaryv c I nk axle 'I 0 I connected at its forwardend with he'traictori2iior vertical pswinging movementfab'out a, f transverse" axis.

I Preferably, the c'rank'axle' IfII'I is provided with a laterally bent; whichjis received'in a sleeve sectionfIflS formed on'or carriedbyfthe -first}gauge; wheel crank axle, .f 'As best shown in Figures 2.;to' .5,' t he sleeve section I03=is" dis-' posed quite close'flto'the' axis defined by the sec- 1110112 45 1 of f trieflcrank .axle f .44, "whereby vertical limits, occasion. 0f t s usewh, I I .r tioned gauge} whee 30 swin ing; movement 'oif the crankaxle- I0 I relative'. to the other 'rankiaxlelldoes' not;-within' terialjiongitudinal "movement 00; elative to t he first men- Normally, fboth crank axles. and'IIl w gtogether a's'fthe plow r ises fall relative to the tractor. However, :whenthe hand lever15'is shifted-forwardly toxcause the power liftrock shaft I6 to-be rocked'in; a clockand falls relative nf-th .eren flax i is in line with the laterally idirect ed sectiori III! ,on whichthe' wheel l'tm s fiournaledil igure 1)-. -A link IIIJlhaving a' drum 'sectien [II I has a: slot II2; formedin,thelatterjto receive the I06 I ,iwmcn xtends.loi tward yjthmugiiithe slot I n. wisedirection; after the shallow; plowing position (FigureS) has been passed, the swivel block 8| The lower end or, thejlin is held infposition 1 .f orpijyotin gfland sliding m" ementfo'n the pin includingthe gauge wheel 30,-into its transport position, as indicated by dotted lines in Figure 3'. r From the latterfigure, it will beseenrthat the arm II and the link III move into substantially, a straight line relation as the plow bottom 22 is adjusted 'forshallow plowing. This construe-, tion 'results'in the advantage that further rockingmovement of the 'powerlift'rock'sh'aft I6 causes very little additional movement-of the bell -crank.51 beyond'that shown in Figure-23, and; I from thisfigureit will also be seen that for shal- ,low plowing position the'links or arms= 3l and; 32 also approach 'their"straightline position, so?

- that whateverflittle movement that does=occur when the implement I i's'raised intoits transport; '11,. has substantially no efiect upon moving e the gauge wheel 30 downwardlyinuchbeyond the point ofthe plow b tt m 22 .The above described anism serves to adjust the'op'erating depth'of penetration of the plowbottom 22"and the sub sequent range of movement serves' to lift both the plow bottom and the gauge' wheel itself out of ground engaging positionis substantially. the

"tructui'e" by which the 1, first range of movement of the'power lift mechts by. a washer in 4 and setter key, or by. any" ot ally connct'edto' upper 1ink I2 I, whichektendsf g ierally longitudinally. ,and f orwardly tothei'lower end I 22' of -a-hand i lever l23, beingconhected 't'othelower end I22 by;-a pivot 1241, The hand lever jl 23' 'is' mounted for rocking'moveme'n on the leftf'end' of-the rock the hand lever; carriesffthe usual detehtmechanism I26 .by' which th lever I 23 may be latched to a sector ,I 21 f'w'hic part ottheleftbracke shaft iili. A ,c'ollar .KI3 orjother suitable means serves toholdtne lever I23 onjthe'ro ck 'shaft 5a.

jis fixed tqor'formed as a that'fsupport'sithe rock A hell cr nk is rs nymommies-at I36,

are, disposed on opposite. si'de's of andr'eceive the a dr m s we -I V I39-0f the: bellcr'ank'I35ispi'voted;"as at MI, .to; the rear end'oi f ,7 I42 that isfpivoted'jas at] I 44, to the lower end of an arm 145, the upperend'of which is'fixed as by welding or the like, toa sleevef-Illi dis'posed .for rocking movement on the rockable shaft or ifthelink I I The other arm ,forwardlyext'e'nding link :means I2 in its intermediate turn,

I falling movement of the 'sinks into the ground, permitting the 7 fixed by the detent mechanism is held against rearward pull on the bar'iltas best shown in Figure 1. The arm I45 is: fixed to the left end of the: sleeve I46, and to the right end of the latter a second arm I4! is fixed. as by welding or the like. The arm I4! is connected by a link I48 to actuate valve mechanism indicated in its entirety in Figure 1 by the reference numeral I50. Thisyalve mechanism, as will be explained below in detail and is shownmore clearly in Figures 7 and 8, serves i to place the valve means I2 under the control of the gauge wheel I and its position relative gto the pivot I20 on the plow beam bracket 31. As clearly shown in Figures 1 and 2, in-normal operating position, 'eitherdeep plowing (Figure 4) or shallow plowing (Figure the two'gauge' 1 wheels 30 and I00 operate alongside one another,

withthe pin I06 disposed in,the central portion of the slot I I2 in the drum section II I of the link IIII. This disposition of the drum section III relativeto the pin I06 serves to hold/the bell *crank I35 in its intermediate position, and as will be explained below, this serves tohold the valve position which, in acts to holdthe power arms 3| and 32 are held in their adjusted position. whereby the gauge wheel 30 (Figures 2 and 3) is held in its proper position. Thus, unless the hand lever is operated, so long as the two gauge wheels 30 and I00 operate at the same level, all of the depth adjusting and varying connections are, so to speak, held in status quo. This does not,.however, interferewith the ability of the implement I to rise and fall as a unit relative to the tractor, for,itwill be observed, particularly fromFigure's I02, adjacent to the pivot axis defined by the front end 45'of the crank axle 44; Hence, rising and implement I relative to the tractor can occasion nomaterial longitudinal .4 and 5, that the pivots movement 'of the links '35, I2I,' and I42, and

therefore all of-thevalve operating parts remain in their neutral or intermediate position. If it should occur, however, that the plow should strike soft ground so that the weight of the plow and associated, parts. would bear sufficiently heavy on the gauge wheel 30 and cause the same to sink into the ground, this would; as is obvious,

;'permit the plow bottom, 22 to operate deeper than the desired depth. There is no appreciable .load on the gauge wheel I00, notwithstanding the factthat the gauge wheel 30carries the weight of the implement, and hencewhen the wheel 30 sinks into the ground under the conditions assumed, the other gauge wheel I00 remains on the surface. However, ifthe gauge wheel 30 plow botiom;22 and the beam to lower, the point I20 (Figure 4) also lowers. The forward end of the link I2I is pivoted at the point I24 to thelower 1m shaft is, and through it and the bell crank 51, the longitudipally extending link 35 and the toggle links or constitute a bell crank, to swing in a counterclockwise direction (Figrue 4), exerting an upward thrust-through the link I48 which, as will be explaindbelow in connection with the de tailed description of the valve mechanism I50, rocks the valve mechanism in a direction to cause-the rock shaft I5 to be shil'ted in a direction to raise the plow bottom 22. this being accomplished by a movement of the powerlift rock shaft I6 and interconnected arms 'II and 12, in

a clockwise direction as viewed in Figure 2 and in a counterclockwise direction as viewed in Figure 4. When this actionof the raising and low ering mechanism brings the point I20 up to its former distance from the ground surface, the

' lower drum section III of the link I I0 is moved so that the bell crank I35 is restored to its neutral position, whereuponfurther raising action ceases. In this position, therefore, the implement is operated with the plow bottom 22 at the desired depth, but with the gauge wheel pressing into the ground an amount sufficient to carry the load. Now if the ground should become harder the gauge wheel 30 then will ride on the surface, as it normally does. Momentarily,.therefore, the point I20 now is-raised above its, former point, shifting the drum section II I in the other direction relative to the pinI06 and rocking the bell crank lever I in a counterclockwise direction Figure 4). which acts through the valve controllng means I-to cause the power lift rock shaft IE to rock in a downward direction lowering-the plowrelative to the gauge wheel 30 until normal positions (Figure 1) are resumed.

with the two gauge wheels 30 and I00 alongside one another.- Figure 6' illustrates in full and dotted lines the action just described.

I24 and I441 are all disposed in or closely 1 Thus, the auxiliary gauge wheel I00 and associated connections operate to maintain theplow bottom 22 at substantially constant depth, regardlessof the ground surface, whether soft or hard. In reality, the gauge wheel I00 and as- "sociatedparts serve as means responsive to the distance between the point I20, and hence also Ithe plow beam 20 and the furrow opener 22, I

and the ground surface and controls the hydraulic power lift connections so as to maintain this 7 distance constant at all times.

different positions.

For figgample, assume that the plow bottom 22 hasjifi ecn "rating in deep plowing position, as h wn i "u g, --.2 and 4. audit is desired to end. I22 of the lever I23, -and since the latter is I26 the link I2l longitudinal movement. Therefore, when the point I20 lowers, the link H0 is tive to the gauge wheel I00 which remains on the. surface. The downward movement of the pivotl20causes the'drum section III, received betweenthe two parts I31 and I38,'to swing the. bell crank; lever 135m a clockwise direction (Figure 4) about "its ivatIsa-"This "exerts a link I42 which, in turn,

causes the arms I45 and I41, which in reality forcedina generally'downward direction rela- In order to adjust the implement for plowing at different depths, the lever'l23 is-moved to Figure 4 shows the deep plowing positionand Figure 5'shows a shallow plowing position. Moving the lever I23 from one position to another, not only automatically adjust the plow for plowing at that new depth but, at the same time, acts-to raise or lower the plow so as to bring it from its oldposition into the desired position. This is accomplished by the linkagesand valve mechanism just described.

have the plow run more shallow. Th operator will disengage the latch mechanism I26 (Figure 1) and move the lever I23 rea1wardly one or more notches. Assuming that the plow is already in operation, it will" be seen from Figure 4. that as'soon as the lever I23 is moved rearwardly.

'the link |2I is shifted forwardly and exerts a thrust against the pivot I20 forcing the drum section III downwardly relative to'thepin I06. This immediately rocks the bell crank I3 5 in a clockwise direction (Figure 4) which raises the plow as described above. If. the lever I23 is moved rcarwardly ahead of the action of the as aias rock'shaft I8 and associated parts operative to I11 of a link I18. Th e' upper' end'of the latterl raise the plow, the latter will be continually v raised until it occupies its highestor most shallow plowing position,- as shown in Figures 3 and 5. The operation of increasing the plowing depth is the reverse, as will be readily understood. It

is an important feature of this invention-, not

'outfltand without being called upon Itof, exert any great amount of force. The only force-required to be overcome is the resistance ofiered by the valve controlling mechanism I50, and similarly this is the only force which the gauge, wheel I is required, to sustain, and from this.

fact it will-be understood that the gauge wheel I00 remains on the surface of theground, no

matter how soft it may at times be.

I have described above the construction and manner of operation of the mechanism that responds to the position of the plow relative to is slotted, as at I 8|, and receives a pin I92 that.

. is fixed to the laterally innerend' of a bracket I93 fweldecl or otherwisefixed' to or formed on the powerlift arm'12, as best shown in Figure 1. c A rib I84; serves to reenforce the arm I83.

An arm' I90 is disposed laterally outwardly of the cam arm I12 and is provided with a hub 0 section I9I and an axially inwardly extending tongue I92. The tongue I92 extends from the.

laterally inwardly extended-portion I9Ia (Figure The innersection of the an-axially directed slot I93formed in the collar IBIYon the shaft 12a. Hence, when the parts valve shaft 1211 in one direction or the'other.

- A spring 196 iscarried at the outer end of the the ground for automatically maintaining the plow at a constant depth of penetration, acting 4 into its transport position. It is desirable, therevalve shaft 12a and at its inner end bearslagainst the arm I90 and at;its outer end bears against a washer I91 heldon the shaft I2a by a cotter key I98 or any other suitable means, The outer endof the arm I90receives the upper end of the link I40, the lower end jof which is connected to the arm I41; Hence, the'position of the arm fore, to provide means whereby. the automatic depth control is itself automatically disengaged when the hydraulic power lift mechanism "has operated to raise the plowbeyond its operating position and begins raising the. same into its transport position. The automatic valve con- I I2 (Figure 1) forms a part ofcr is fixed to a gaug' I90 is controlledby the'movement of the gauge the other gauge wheel 30.

The operation of the automatic valve controlling mechanism I50 now be described.

2 and associated parts will proper depth and the ground surface is suiii--' ciently firm to support'the first-gauge ,wheel' 30 on thesurface thereof alongside the controlling valve actuating shaft, shown at. I2a in Figures or holding it against movement in at least one direction in any intermediate position. The details of-such hydraulic mechanism do not per se form a part of the present invention, and hence of the power lift in either direction, as desired,

gauge wheel I00, the parts, assuming deep plowing positionfareas indicated in Figure l, the; pin I00being disposed in the intermediate portion of the slot I I2, which causes the bell crank I35 to actthrough the-link I42, the arms I45 and I41, and the link I40 to hold the arm I90 (Figure 8), and hence the valve shaft'IZato its intermediate position. This looks the hydrauhas not been described. T The valve shaft}I2a ex-' tends laterally outwardly from the right side of the valve housing I1 and at the point where it emerges from the valve housing I1 the shaft I2a is provided with a collar I6I securely fixed to or formed on the shaft -I2a, the collar IGI wheel 30'will1sinklih, somewhatas shown in full lines in Figure 6, H ver, the controlling lic mechanism jagainst movement and hence holds the rock shaft ltfand the arm 12 in adjusted position. Assumingxnow that, the ,piow 1 strikes a soft spot: The plow suppor'tinglgauge gauge wheel I 00," which sustains no load, remains on the surface-of the groundgand as pointed out being rotatable with the'shaft In at all times.

Surrounding the collar I6I is a first cam mem ber-I62 which includes an arm I63 and a ring member I64 having a plurality of cam. sections I66 and dwell sections I61. The arm I 93 at its lower end is bifurcated, as at I68, and engages a stationary pin I69 fixed to the right side of the valve housing 11 for the purpose of holding the cam member I62 against rotation. If desired, the cam sections I 66 could be formed directly on or fixed to the casing I1 or some other convenient part, instead of being carried removably, as shown. Next outwardly of the cam member I02 is a companion cam member I12 of above, the sinking in of thegauge' wheel 30 and I the consequent lowering of the. pivot point I20 serves to force the drumsection I I I of the link II 0 downwardly, thereby rocking the bell crank lever I35 from its dotted line position (Figure. 6) -to its full line position. This'acts through the link I42, the arms I45, I41and thelink I40 to rock the arm I90. The latter, in turn, rocks the valve shaft I'Za, the mechanism being arranged so that thismovement, that is, the upward movement of the arm I90, operates the hydraulic mechanism in a direction to raise the plow beam 20, as by rocking the shaft I6 and arms 1| and similar. construction, embodying a ring section 7 12 in'a clockwise direction (Figure 2)., forcing the link 10 rearwar'dly and pullingforwardly on V j the link '35,jthus.raisingtheplow20back to its original position, shown in dottedflines-inFigure 6.. This restores the pivotpoint I20 into its original position relative to the ground surface, and hence the drum section III of the link ,I I moves back into its intermediate position and acts through the links I42 and, I48 and associated parts to return the valve controlling arm I90 back to its intermediateor locked position. After the outfit has traveled beyond the soft spot, the gauge wheel then rides up to the surface of the ground, and in doing so starts to raise the plow bottom 22 to a more shallow plowingposition than that calledfor by the position of the adjusting lever I23. As soon, therefore, as'the pivot point I20 starts to move higher than its determined position relative. to the ground, the

"drum section III of the link H0 is pulled upwardly, until the pin I06 lies in the lower end 7 of the slot II2. This swings the bell crank lever I in a counterclockwise direction (Figure 6) which exerts a forward thrust on the link I42, pulling downwardly on the link I48and swinging the arm I90 in a downward direction,' which now rocks the valve shaft I2a in the other direction, which causes the power lift} mechanism to be actuated to lower the plow until again the point I20 on the plow is disposed at the required dis-- tance above the ground surface, and when the proper position is reached, the valve mechanism 2 is again automatically locked to hold the plow i the upper end of the link II8. However, when to force the member this movement of the member I12 axially of the shaft serves to disengagethe tongue I92 (Figure 8) from the slot I93. As soon as the tongue I92 leaves the slot I93 the adjusting'arm I90 is, of course, no longer connected to thevalve shaft I2a, and hence the position of the pin I06 in the slot II2 has no effect upon the actuation of the valve mechanism. However, when the plow is returned tooperating position, a small spring 2I0 (Figure 7) pulls downwardly on the arm I'I6 so as to return it into a position permitting the spring I96 I90 laterally inwardly, carrying the tongue I92 into the slot I93 as soon as the power lift arm I2 returns to its depth adjusting range, whereupon the control of the depth of. plowing is returned to the gauge wheel I00 by the time the latter and, the plow, supporting gauge wheel &30 come into contact with the ground. t

It will thus be apparent that, according to the principles of the present invention, I have prothe power lift arm I2- moves into its shallow plowing position (Figure 3), the pin I82 is at the upper end of the slot I8I (Figure 7). Now, Kit is desired to raise the plow, together with both of the gauge wheels 30 and I00, out of plowing position and intotransport position, the hand lever I5 may be actuated, as'by moving the same forwardly, which operates the valve shaft I2a directly' through the arm I9 and the link 80 (Figure 1). The forward movement of the hand lever I5 causes the hydraulic mechanism to rock the lifting shaft I6, and the latter in turn acts through the lifting arm I2 to raise the plow into its transport position (dotted lines, Figure 3). At this time it is desirable to disengage the hy- .draulic valve means from the mechanism automatically operating the same when in plowing position; otherwise, when-theplow is raised into its transport position, the gauge wheel I00 being no longer supported on the ground would tend to pull the pin I06 down into the lower end of the slot H2, and causing the power lift immediately to lower. In order to effect an automatic disconnection when the power lift mechanism of the tractor starts to move in its raisingrange,

the cam members I62 andIIZ have been provided,-the former being held against movement by the pin I69 and the other being connected through the link II8 with the lifting arm 12 by the lost motion slot and pin connection I8I, I82,

mentioned above. When the arm "starts to raise the implement, the pin I82 engages the upper end of the slot I8I and raises the outer end of the arm I16. .As best shown in Figure 8,

this movement is in a direction to cause the cam w teeth I66 and I14 to force the *member -II2 to the left. Since'normally the member H2 is disposed against the controlling arm I (Figure '7) vided an agricultural machine of the soil working type with means for automatically maintaining a constant depth of adjustment while, at the position automatically causing the plow to shift into that position without any other act on the part of the operator. However, the power lft mechanism of the tractor is utilized and'itsmovement divided, generallyspeaking, into two parts, the first movement serving to effect the required adjustments to secure a constant depth of. plowing or to move the plow: to. different depths, as desired, and the second movement being utilized for raising both the plow'and the gauge wheels into transport position and out of engagement with the ground.

It will-therefore be apparent that, while I have shown and described the preferred structure in which the principles of the present inventionhave been incorporated, the present invention is not to be limited to the particular details shown and described above, but that, in fact, widely different means may be employed in the practice of the broader aspects of my invention. What I claim, therefore, and desire to secure by Letters Patent is: a 1. An agricultural machine comprising a tractor, a ground working tool movable relative thereto, ground engaging means separate from the tractor and movable along theground surface with the tool for supporting said tool at various depths of operation, and means responsive to a change in the position of said tool relative to the ground and including a part on the tractor for shifting said ground engaging means relative to the tool for the purpose of keeping the latter in operation at'a substantially constant depth.

2. An agricultural machine comprising a tractor, aground working tool movable to different operating depths, a gauge wheel movably connected with said tool, means acting'between the latter and said gauge wheel and including a part on the tractor for raising or lowering said tool, a'second gauge wheel movablyconnected with said tool and adapted to ride along the ground surface, and mechanism controlled by said sec.- ond gauge wheel 'for actuating said part so as to control said raising and lowering means.

' 3. An agricultural machine adapted to be connected toa tractor having tool raising and lower ing means thereon; comprising a ground working tool,- means connecting t-helatter with said trac tor and said raisingiand lowering ,means, and

means engageable with thegroundsurfacefor automatically operating said-raising and lowering means so as to maintain said tool at the de-' sired depth, said connecting means accommodating relatively free vertical movement of said tool relative to thetractorgsaid means for op erating the raising and loweringmeans including relatively movable parts, certain of which normally move with said tool relative tothe tractor and other parts-connected with said rai'singand lowering means, said latter-being controlled ir-' respective of the relative position between-said tool and tractor. I i a i v 4. An agricultural implement comprising-"a tractor, a ground working unit including a tool beam movablyrconnected with the tractor and 1 one of: said gauge wheels for raising-an lower ing the furrow openergand means, controlled by the position-of the other gaugewheel relative to the IploW beam for actuatingsaid. mechanism i 7-. Anagricultural machine i-comprising means servingas an implement frame, a ,plow, beam ,pivgotally :connected thereto 1 at;tit s ,forward end, mechanism ';for Praising and lowering said plQw beam,; a part movably connected withsaid beam, manually; adj ustable. means \for jcontrollingjm position-ofsaidipart, ground engaging:;means movably connected with said part and adapted to traverse the ground-surface alongside rsaid beam,=,and.means, controiledybyz the relative ;position, oftsaid ground engagingmeans awith reispect to said part for actuatin said, raisingand lowering mechanism; I 8. vAn agriculturalmachine comprising a tractor having apowerilift, tool means onnected with the tractorformovementrelative theretoameans deriving. DOWEILIIOHI;"fl'l lilflfilibl" power. lift and operative, through 'a,-zfi-r. tgranee of: movement for adjusting thedepthzofeoperationi of ,said tool ns. and lpperatiyeethropgh another; range of movement .afor ,raisinggandrloweringysaidptool means, means; including-a ground, engagingtpart for automaticallyv r-controlling; said adjusting tor about an axis disposed'approximat'ely'adjacent said, tool beam, mechanism carried by the tractor for determining the position of said gauge wheel relative to said too1 beam, includmg"-'a part movable from one position to another adjacent said. axis and a link extending fromsaid part generallyparallel with said tool beam"to isaid gauge wheel, whereby movement of said tool beam and said gaugewheel relative'tothe tractor will have no material effect upon the position "of-the gauge wheel relative to said tool beamgmean'son the tractor for operating said mechanism, ,inicluding'a movable part disposed adjacent "said axis, andiaground engaging element m'ovably connected withsaid beam and with said last men"- tionedpart, whereby saidmechanis'm" may be actuated: by said last mentioned means so' as-to maintain said tool beam and said tool :ineans in proper operating position relativetothe ground independently of the position of said tool beam relative to the tractor; v

5. An agricultural machine comprising means serving as an implement frame, aground working tool movably connected therewith,'-ground' engaging gaugemeans movably connected with "said tool, longitudinally extending link means operaftively connected with said gauging means for varying the position of said tool relative to the ground, mechanism" on said frame-means'for shifting said longitudinallyextendinglink means, asecond gauging meansdisposed along'side said t first gauging means and movable-relative tcTsaid tool, andmeans operated by movement of said second gauging means relative to said tool for actuating said mechanism, said last named means including a part mounted for adjustment 011 said frame means, a ground engaging member and a connecting link between said part and saldmemberextending generally. parallel with 'respect to said link means.

6. An agricultural machine comprising means serving as an implement frame, a plow beam movably connected therewith at one end and having a furrow opener at the other end, a pair of ground engaging gauge wheels movable independently of one anotherand eachb'eing'movablyconnected with said plow beam, mechanism acting through means throughout its adjusting range, and means for disabling ,said :last; mentioned meansrwhen said adjusting means :Loperates. and :enters? its serving as an implement; frame, tool meansmovably, connected withsaid frame means and adapted;to be raisediand'lowered,;gauge "means for said tool meanaumechanism onsaidrframemeans operative through one. rangeyof; movement for shifting said ,gauge rneansrrelative; to saidtool means for gauging the, depth of-goperation there; of, a second-gauge means movablyiconnected with said ,tool means; means {responsive to relative .movement of the-gsecond gauge wmeans witlivrespect to said tool meanszforaactuating said mechanism, separate, means for actuating said mechanism through another: range of 1 movement; and meansactuated byimovementof said mechanism through its other rangeof'movementfor raising both 1 gauge. means and said: tool means but 1 of ground engaging position.w I

,9, furthercharacterized by;means1 for throwing .sai dsecond gauge means but of operationiwhen the means for operating said first gauge means move into a second, rangeaiof-movements, .11. An agricultural machine comprisin'gia: tractor, a" ground working tool disposed generally longitudinally: of the tractor'and pivotally connectedtherewith for, vertical; swinging movement, a crank axle pivoted; to =the tractor for vertical iswingingjmovement about a: transversaaxis, dis.- posed generally. in; a-line between said tool "and its ;connection,.with: thetracton'a gauge wheel ,mounted on the outer end-"of: said:-c-rank' axle,

shiftable connections between said: gauge] wheel and said tool, :means' on :the tractor-"op'eratively connected? with said connecti'ons 'and reacting therethrough against the gauge' Wheel for raising I and lowering said-tooka-second gaugewheelja crank axle therefor pivotally' connectedwitlfthe tractorfor movement'with and relative tosai d first crank'axle, connections between said second 7 10. An agricultural machineaskdefineeinclaim 5 movement of said-last mentioned connections for operating said raising and lowering means.

12. An agricultural machineas defined in claim 11, further characterized by said last mentioned means being mounted on the tractor, and both said last mentioned means and said raising and lowering means being connected, respectively, with their associated connections at points adjacent the pivot axes of said crank axles, whereby both of said gauge wheels swing vertically with said tool relative to the tractor without causing any material change in the positions of said connections.

13.4An agricultural machine comprising means serving as an implement frame, a ground working I tool movably connected with said frame means for vertical movement relative thereto, means for raising and.lowe'ring=said tool means,- gauge means, a crank axle carrying said gauge means I and connected with said frame means for movement relative thereto about a pivot axis, connec-- tions carried by said tool means and movably associated with said gauge means, and meansop erated by relative movement between said conf nections and said gauge means for operating said raising and lowering means, said last mentioned" means being mounted on said frame means and operatively connected with said gauge means by relatively movable parts pivotally connected together about an axis coinciding with the pivot axis of said crank axle, whereby said gauge means is free to move with said ground engaging tool;-

power lift through another range of movement for raising said tool to inoperative position, and means actuated by movement of said power lift into its second range of movement for releasing said gauging means from its connection with said valve controlling part.

15. An agricultural implement comprising a tractor having a motor, hydraulic mechanism driven by the tractor motor and including a shiftable part, hydraulically operated means for shifting said part, and valve means controlling said hydraulic means and serving to control the shifting of said part from one position to the other and to hold the same in intermediate positions against movement in at least one direction, a ground engaging tool movably connected with the tractor, mechanism for raising and lowering said tool, means connecting said mechanism with said shiftable part, gauging means responsive to the position of said tool relative to the ground surface for controlling said valve means so as to cause said hydraulic mechanism to automatically operate said raising and lowering means and maintain said ground engaging tool at substantially constant operating depth, separate means for operating said valve means, and means controlled by the movement of said shiftable part beyond a given range for automatically-disconnecting said gauging means from- -s aid'--valve 16. An agricultural machine as defined in claim 15, further characterized by 'said responsive means-comprising a pair of relatively rotatable cam elements, means for holding one of said elements stationary, meansconnecting the other element with said shiftable part, and means whereby relative movement of said elements beyond a certain amount automatically disengages said gauging means from said valve means.

17. An agricultural implement comprising frame means, a ground working tool movably connected therewith, a pair of crank axles pivotally'connected with said frame means, a gauge wheel on the outer end of each crank axle, mechanism reacting against one gauge wheel for shiiting the position of said tool relative thereto, and means controlled by the other gauge wheel for actuating said mechanism.

' 18.- An agricultural machine comprising a trac tor, a ground working tool connected therewith, raising. and lowering means deriving operating energy from the tractor and reacting against the a ground separately from the tractor .for raising andlowering said tool, andgauge means responsive to changes in the. operating depth of said tool" for :operating said "raising and lowering means.

19. An agricultural machine comprising a ground working tool, means for raising and lowering said tool in operating position and including means engageable withand reacting against the ground, the reaction of the tool tending to cause said means to sink into the ground when the tool tends to rim too deep, and means also engageable with the ground adjacent said first ground engaging means and responsive to changes in the position of said first and second ground engaging means for controlling said raising and lowering means. i

20. An agricultural machine comprising a tractor, tool means movably connected therewith,

adjustable means including an operating unit on the tractor for gauging the operating depth of said tool means independent of variations in the position of the tractor relative to the tool means, and means responsive to changes in the operating depth of said tool means for adjusting said depth gauging means. I

' 21. An agricultural machine adapted to be connected to a tractor having tool raising'and lowering means thereon, comprising a ground working tool, draft means connecting saidtool with the tractor for relative tree movement with I respect thereto, means on the tractor and connected with said tool for raising and lowering the latter substantially independent of variations in the position of the tool relative to-the tractor,

means responsive to changes in the operating depth of said tool, and 'means connecting said depth responsive means with said raising and lowering means and accommodating the relative free movement of the tool relative to the, tractor for automatically operating said raising and lowering means so as to maintain said tool at the desired depth,

22-. An agricultural machine comprising a tractor having a power connection, tool means connected with the tractor for movement relative thereto, means deriving power from the tractor power connection for adjusting the depth of operation of said tool means. means including a ground engaging part for automatically controlling said adjusting means, and means for disabling said automatic controlling means and raising said tool means into inoperative position.

23, An agricultural machine comprising a tractor having a valve-actuated hydraulic power connection, the latter including a valve controlling part, a ground working tool movably connected with the tractor, means connecting said tool with said power connection whereby operation thereof through a first range controls the depth of penetration of-the tool, gauging means connected with said valve controllingpart for actuating said power connection to automatically control the position of said tool, and means actuated by movement of said power lift through another range of movement for raising both said tool and said gauging means to inoperative position. l

24. An agricultural implement adapted to be propelled by a tractor, comprising an earth working tool, means connecting the latter with the means responsive to changes in the position of" tractor for generally free vertical movement relative thereto, and means actuated by the tractor motor and responsive to the position of said tool relative to the ground for auomatically maintaining said tool at approximately constant Working depth during operation, irrespective of .relative movement between said tool and the tractor.

25. An agricultural machine comprisinga tractor, an implement movably connected therewith and including tool means and ground engaging means determining the operating depthof said vertical movement relative thereto, a power unit deriving energy from the tractor and adapted to control the working'depth of the tool means in a the ground in any vertical position of the implement relative to the tractor, and control means for the power unit and sensitive to variations from a predetermined operating depth of the tool means for causing the power unit to function to maintain said tool means at said predetermined operating depth, irrespective of movement of the implement relative to the tractor.

27. In combinaion, a tractor,'an agricultural implement having ground working tool means and connected with the tractor for generally free vertical movement relative thereto, means on the implement for raising and lowering the tool means to vary the operating depth thereof, a power unit deriving energy from the tractor and adapted to control said implement raising and lowering means, and control means for the power unit and sensitive to variations from a predetermined operating depth of the tool means for causing the power unit to function to maintain said tool means at said predetermined operating depth, irrespective of movement of the implement relative'to the tractor.

28. An agricultural machine comprising propelling means, implement means connected therewith for swinging movement relative to the propelling means about an axis, and including movable ground working tool means, means on the implement for adjusting the operating depth of said tool means, means on the propelling means for operating said'adjusting means, connecting means between said adjusting and operating means, said connections being disposed adjacent the axis of said swinging movement of said im said connections and raise said tool independently of the position of said ground engaging part of said tool means, for actuating said operating j m eans.

29. An agricultural machine comprising an op-. erating unit, means for raising and lowering said operating unit relative to the ground surface,

said operating unit relative to the ground surface for controlling saidraising and lowering means, means for raising said operating unit into a transport position, and means responsive to actuation ing means and including a part on the tractor, 1

a ground engaging part and connections between said parts, means for adjusting said connections so as to adjust said tool for difieret depths of operation, and means operative to 'disconnect relative to said tool.

31. agricultural machine comprising a tractor, a ground working .tool connected therewith,

movin said tool into operating position for restoring the operativeness of said depth responsive means.

32. An agricultural machinecomprising a tractor, a ground working tool, means on the tractor forraising'and lowering said tool, ground engaging means movable relative to said tool in response to changes in the depth of operation thereof, connections between said ground engaging means and said raising and lowering means for automatically operating the latter soas to main:

tain a desired depth of operation, means adapted. I to disable said connections and to raise said tool into transport position, and means operative when said tool moves out of transport position and into an operating position for restoring the operativeness of said connections the depth of operation of said tool.

33. An agricultural implement comprising a tractor, ground working tool means connected with the tractor for generally free vertical movement relative thereto, operating means including ground-engaging gaugemeans for adjusting the depth of operation of said tool-means in any position of the latter relative to the tractor, ground engaging pilot means movable relative to said tool means and responsive to changesin'the depth of operation of the latter, and means controlled by movement of said tool means relative jto-said i I pilot means and reacting against said gauge,

means for adjusting said operating means, 34. An agricultural machine comprising a tractor, a ground working tool means on the tractor for raising and lowering said tool and operative through two ranges, ground engaging means mov- I able relative to said tool in response to changes in the depth of operation thereof, connections between said ground engaging means and said so as to control raising and lowering means for automatically operating the latter through one range and maintain a desired depth of operation, means to operate said raising and lowering means through the second range, means controlled by movement of the raising and lowering means in the raising direction through said second range to disable said connections, and means operative when said raising and lowering means moves through said second range in the lowering direction for restoring the operativeness of said connections so as to control the depth of operation of said tool.

'35. An agricultural implement comprising a tractor, a plow beam movably'connected therewith at one end and having a furrow opener at the other end, means including a-power unit on the tractor and a part movably carried by the plow beam and adapted to engage the ground for controlling the depth of operation of said furrow opener, means responsive to the depth of operation of said furrow opener, and connections between said depth responsive means and said power unit whereby the operation of the latter is controlled by the depth of operation of said furrow opener.

36. An agricultural machine comprising a tractor having a power connection, tool means connected with the tractor, means reacting against connected to a tractor having a power connection,

said implement comprising ground working tool means movable relative to the tractor, ground engaging gauge means movable with said tool means relative to the tractor, 'means adapted to be carried by the tractor for raising said tool means, a part to be connected with said power connection on the tractor, connections between said part, gauge means and raising means whereby movement of said part by said power connec tion through one range controls the operating depth of said tool means and movement of said part through another range actuates said raising means, and means responsive to changes in the operating position of said tool means for controlling said part through said one range.

38. An agricultural implement adapted to be connected to a tractor having a power connection, said implement comprising ground working tool means movable relative to the tractor, means for adjusting the depth of operation of said toolmeans, separate means for lifting said tool means into raised position, a part to be connected with said power connection and operative through one range to actuate said adjusting means and operative through another range to actuate said lifting means, depth responsive means connected to actuate said power connection and move said part to difierent positions in said first range, means for actuating said power connection for shiftingsaid part through its other range of movement to lift said tool means, and means responsive to movement of said part through said second range of movement for disconnecting said depth responsive means from said power connection.

39. An agricultural implement comprising tool means, mechanism for raising and lowering said including separable parts connecting said respon-,

sive means so as to adjust the operating depth of said tool means, and means for separating said separable parts when said mechanism raises said tool means into its inoperative position.

' 'I'HEOPHILUS BROWN. 

